I need to know what the capacity for the np 233 transfercase is. most gm dealers tell me 2.3 qts the only issue is I drained it and it will only hold about
a quart before it comes out the fill hole.I just want to know how much it should take

Check the Haynes or Chilton. If you can only get a quart in, then you may have it air locked. My boat outboard does the same thing on the lower unit if I fill it too fast. try using one of those cheap pump attachments that fits on a quart of oil. Slowly pump it in and see if you cant get it all in.

-- 2001 S-10 ZR2. Too many mods to list. It upsets me too much to add up all the money I spent.

man your a real genius s10dude ! I said I filled it to the fill hole not the drain hole. when the gm shop tells you it take twice the oil you can put in it should make you ask a few questions don't you think? mabe it has two chambers?
or something else I'm over looking but hay I got your great insight huh.
just happens I found that it is in pints so anyone looking for a straight answer a np 233 transfercase takes 2.3 pints of auto track-2 oil not quarts

It takes 1.25 QUARTS. In some places, the genuine service manual from GM incorrectly states the amount required for the 236 transfer case (which takes the new type fluid and 2.3 quarts). Since the 233 drain plug is not at the 'very bottom' of the case, you may not be able to get 1.25 quarts back in after draining.

The 233 takes Dexron III. And DO NOT put in Dexron VI as I did, thinking I was doing the case a 'favor'. Apparently, the DEX VI is too thin (too low a viscosity).

Since GM no longer licenses DEX III, GM has stated not to use any aftermarket fluid 'recommended' as DEX III use. Actually GM has simply relabeled its own DEX III as "manual transmission and tranfer case fluid". I do not have the part number handy, but you should not need it at a dealer parts shop. I really wonder who is making the GM 'official' fluid, since obviously GM does not. This is a mineral base fluid, not a synthetic.

My dealer is pushing BG Synchro Shift II for the 233 transfer case. This fluid is full synthetic. It is rated as 75W-90 gear oil API GL-4, and also as meeting GM Synchromesh spec 9985648 P/N 12345349. Unfortunately it costs $20 a quart, and you will need two.

What other fluids are people using in the New Venture 233 transfer case?